Metal cutting and grinding apparatus



Jan. 26, 1960 H. c. ELSE METAL CUTTING AND GRINDING APPARATUS Filed July 11, 1957 INVENTOR. H9212 r C. E1. 65

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' METAL CUTTING AND GRINDING APPARATUS Harry Calvin Else, Pittsburgh, Pa.

Application July 11, 1957, Serial No. 671,237

3 Claims. (CI. 51-44) This invention relates to apparatus for cutting or grinding metal, and more particularly to means for preventing overheating of the work.

In grinding or cutting a metal workpiece with a rotating abrasive Wheel, the metal may become very hot where the wheel is in engagement with it. This overheating of the metal interferes with satisfactory work. The overheating is produced byfriction, whether the wheel is cutting through the metal or merely grinding its surface. Therefore, although this invention will be described as cutting apparatus, it is to be understood as including grinding apparatus.

It is among the objects of this invention to provide metal cutting or grinding apparatus which will not overheat the workpiece and yet which can be moved at a satisfactory rate across the work.

In accordance with this invention, an abrasive wheel is moved radially across a workpiece by uniformly moving traversing means. Means also are provided for reciprocating the wheel back and forth as the traversing means moves ahead. This periodically retracts the wheel from the front end of the out being made by the wheel, so that cooling fluid can be directed into the exposed portion of the cut in front of the wheel.

The preferred embodiment of the invention is illustrated in the accompanying drawing, in which the single figure is a side view of my apparatus.

Referring to the drawing, a heavy rectangular beam 1 is supportedat one end by a pedestal 2 and at its opposite end by a support 3, on which a suitable driving mechanism 4 is mounted. This mechanism can be designed for driving an endless chain or a traversing screw 5 at a constant rate of speed, and it is reversible so that it can drive the traversing element in either direction. A carriage 6 is mounted on the beam and is provided with rollers 7 that engage the beam so that it can be easily moved along it. The traversing screw extends loosely through the carriage. Above the carriage an electrically operated driving unit 8 is mounted on a platform 9 that can be adjusted vertically by screws 10. This driving unit is connected by a pulley 12 and belt 13 with a pulley 14 at the inner end of an arm 15 that is pivotally connected on the axis of pulley 14 to the lower end of a vertical element .16 supported by the-driving unit. The lower pulley is connected by a belt 17 with another pulley 18 journaled in the outer end of the arm, which extends toward pedestal 2. The outer end of the arm supports an abrasive wheel, such as a cutting wheel 19 that has a guard 29 over it. The weight of the wheel may be counterbalanced to some extent by counterweights 21 on a rod 22 projecting from the inner end of the arm, so that the depth of cutting or grinding can be controlled. Beneath the beam there is a bed 23, on which a metal workpiece, such as a plate 24, can be mounted so that it can be ground or cut in two.

The carriage is moved along the beam by means of a traversing carriage 25 that is movably mounted on the beam in the same way as the driving carriage. The

traversing carriage is threaded on the traversing screw so that it will be moved forward or backward at a uniform speed. This carriage may be connected to the other carriage in various ways that will permit the driving carriage to be reciprocated as it moves along the beam. Preferably, the traversing carriage supports an electric motor 26 and speed reducer 27'that drive a crank 28 continuously. This crank is pivotally connected by a connecting rod 29 to the driving carriage ahead of it.

While the traversing screwis rotating, the traversing carriage 25 is moved slowly along the beam at a constantrate of speed. Through the connectingrod 29, the traversing carriage pushes the driving carriage 6 ahead of it in order to move the abrasive wheel radially across the work. However, unlike the traversing carriage, the driving carriage does not move forward at a uniform rate. Instead, due to crank 28, the driving carriage is periodically moved backward part of thedistance that it has moved ahead. This action therefore periodically retracts the abrasive wheel from the front end of the cut 31 that it is making, whereby the front end of the cut is exposed. During these moments of exposure, cooling water or other fluid pours into the front end of the cut to cool the metal immediately ahead of the wheel. This water, which can also be used for cooling the wheel, may be delivered from a pipe 32 mounted on the wheel guard and connected by a flexible hose 33 to a suitable source of supply. To coo-l the material immediately be- With this provision for periodically flushing out the 7 cut in front of and behind the abrasive wheel, overheating of the metal at those points is avoided. As arm 15 is hinged so that the wheel bears against the work with constant pressure, it cuts while moving backward as Well as forward. Consequently, from two to three times as much material is removed per pass as heretofore. The reciprocating movement of the wheel in the cut produces a'saw tooth type of design at the bottom of the cut as the wheel moves across the work. The resulting line of sumps fills with water to promote cooling.

It will be obvious that this apparatus is not limited to cutting metal, as it also can be used advantageously to cut glass, ceramics, stone and other materials.

According to the provisions of the patent statutes, I have explained the principle of my invention and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as spe cifically illustrated and described.

I claim: V

1. Cutting apparatus comprising a track, a pair of carriages mounted on the track, means for moving one carriage along the track at a substantially uniform speed, means connecting the carriages so that said one carriage will move the other carriage along the track, an abrasive cutting wheel supported from said other carriage, means supported by said other carriage for driving the wheel, said connecting means being formed to reciprocate the wheel-supporting carriage back and forth, whereby to periodically retract the wheel from the front end of the cut, and means for directing cooling fluid into the periodically exposed portion of the cut in front of the wheel.

2. Metal cutting apparatus comprising a vertical abrasive peripheral edge-cutting wheel, means for rotating the wheel on a horizontal axis, traversing means for moving the wheel only radially in a substantially horizontal path across a workpiece below it to make a cut through the workpiece, means for moving said traversing means at a uniform speed, means for horizontally reciprocating the wheel radially back and forth lengthwise of said cut as said traversing means moves ahead, whereby to periodically retract the wheel from the front end of the cut, and means for directing cooling fluid into the periodically exposed portion of the cut in front of the wheel.

3. Metal cutting apparatus comprising a vertical abra sive peripheral edge-cutting wheel, means for rotating the wheel on a horizontal axis, traversing means for moving the wheel only radially in a substantially horizontal path across a workpiece below it to make a cut through the workpiece, means for moving said traversing means at a uniform speed, a crank and connecting rod operative- 'ly connecting said traversing means with the wheel to horizontally reciprocate the wheel radially back and forth lengthwise of said cut as the traversing means moves ahead, whereby to periodically retract the Wheel from the References Cited in the file of this patent UNITED STATES PATENTS 1,100,704 Bartels June 23, 1914 1,778,288 Bicheroux Oct. 14, 1930 1,862,850 Fritschi June 14, 1932 1,914,413 Elbert June 20, 1933 2,195,065 Wallace Mar. 26, 1940 2,236,709 Hillix Apr. 1, 1941 FOREIGN PATENTS 369,354 Great Britain Mar. 24, 1932 

